Technical Field
The present invention relates to a substrate support and heating assembly having heaters for controlling the temperature uniformity of a susceptor of the assembly and a substrate. More particularly, the assembly includes a susceptor assembly, a riser shaft and heaters suitable to effect the method.
Background Information
For many semi-conductor fabrication processes, a semi-conductor substrate or wafer may be heated within a processing chamber. In some instances, the substrate or wafer is seated on a heated susceptor which is secured atop a riser shaft. A resistance heating coil or other heating mechanism is typically enclosed within the susceptor to provide conductive heat to increase the temperature of the susceptor and the semi-conductor substrate when seated thereon.
It is particularly difficult to provide a uniform temperature across the susceptor and the substrate being heated in the processing chamber, particularly with respect to the central region of the susceptor and substrate. Coil heaters which are typically embedded within the susceptor have a minimum bending radius which limits the ability to heat the central area of the susceptor and the substrate. In addition, the riser shaft typically serves as a heat sink which draws heat from the central region of the susceptor and substrate. While some prior inventions such as those disclosed in U.S. Pat. No. 6,744,018 and U.S. Pat. No. 7,126,092 have addressed the control of heating in a similar context, it has been found that there is still a need for the ability to control the uniformity of the temperature of the susceptor and substrate within tighter tolerances in order to provide for the exacting requirements needed for high quality production of semi-conductor components.